Method of making thermometers.



F. J. BERBERICH.

METHOD OF MAKING THERMOMETERS.

APPLICATION FIL'ED JUNE 26, 1911.

1,255,979., Patented Feb. 12, 1918.

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. METHOD OF MAKING THERMOMETERS. I

Application filed June 26, 1917. Serial Ito. 176,953.

To all whom it may concern Be it known that I, FRANK J. BERBERICH, acitizen of the United States, and residing at Woodhaven, L. I., in'thecounty of Queens and State of New York, have invented a certain new anduseful Method of Making Thermometers, of which the following is aspecification, such I as will enable those skilled in the art to whichit appertains to the same.

This invention relates to thermometers, and particularly to what areknown as insulated thermometers, and to devices of this class designedfor use in determining the temperature of liquids, and the object of theinvention is to simplify and 'cheapen the construction of devices ofthis class. without impairing their efliciency, and with this and otherobjects in view the invention consists in the method of formingermometers of the class specified, hereinafter described and claimed.

The invention is fully disclosed in the following specification, ofwhich the'accompanyingdrawing forms a part, in which the separate partsof my improvement are designated by suitable reference characters ineach of the'views, and in which Figure l is a view partially in sectionof a capillary tube which I employ in the construction of my improvedthermometer;

Fig. 2 a similar view of'a casing tube which employ;

Fig. 3 another view and showing the first process;

Fig. 4: a view showing the capillary tube within the casing tube andindicating the secondstep of the process; c i

ig. 5 a view similar to Fig. 4 and indicating the third step of theprocess;

Fig. 6 a view similar to Fig.5 but indicating the fourth step of theprocess;

Fig. 7 a similar view but indicating the of the capillary tube step ofmy improved 'fifth step of the process; and,

Fig. 8 a sectional view of a complete thermometer made according to myinvention.

In the practice of my .invention, I provide a capillary tube a'which-in.all respects is similar to the capillar tube usually employeddevices of t e class under consideration, and the tube a, as shown, isprovided near one end with an offset bend a", but this ofi'set bend isnot essential and may or may not be employed.

or constructing I also provide a casing tube 6 of the form usuallyemployed in the manufacture of thermometers of this class, and this tubeis open at both ends and provided at one end with a reduced taperedextension 6 beyond which, in the construction shown, is a bulbousenlargement b which said tube is further tapered as shown at 6*, but thebulbous is not essential in my importion 6 of the casing b, and the bulba therein, until said parts reach a plastic state and then blowingthrough the tube a and,

exploding the outer side of the bulb a and expanding said bulb to forman open oblong cylindrical bulb member o as shown in Fig. 6, the wallsof which unite with and become integral with the corresponding walls ofthe tapered, portion 6 of the casing tube 6.

The next step in the process consists in closing the end a of thecapillary tube in the usual manner, or by a piece of sealing wax asshown at 0 in.F1g. 6, and then holding the device in an invertedposition, or with the tapered end thereof directed upwardly and pouringa predetermined amountof mercury or other material into the opencylindrical bulb member a through the open end I) of the casing tube asshown at d in Fig. 6,after which the casing tube is marked asshown at eto determine the point at which the end of thecasing, or the bulb membera is to be closed, after which the material a is poured out through theopen end 6* of the casing tube, after which the casing tube is heated atthe point e and manipulated to close said tube at saidpoint and to thusform the complete bulb a shown inFig. 7,. and in this operation the endportion 6 of the. casing tube 6 is broken ofl.

The above described operation reinforces the bulb a. as will be readilyunderstood, and thickens and strengthens the walls thereof, and makesthe same more substantial' and less liable to break than When said bulbisformed by the usual or other process, and said bulb instead of beingof the usual spherical form is of an elongated form; and by forming saidbulb in the manner described'a perfectly smooth, even and curved outletat from the bulb into the capillary tube a is provided, and thisfacilitates the operation of exhausting air and moisture or othersubstances from the bulb.

After the formation of thebulb in the manner herein described, thefinishing work in order to produce the complete thermometer 7' shown inFig. 8 is performed in the usual manner, the mercury being introducedinto the bulb a through the capillary tube a in the usual manner, afterwhich the moisture and air is extractedfrom the bulb and tube and thescale formed or set, in the usual manner, after which the end an of thecapillary tube is closed in the usual manner, as is also thecorresponding end of the casing tube in finishing the thermometer, butinthe accompanying drawing said end of the casing tube is not shown asclosed. It will be understood, of course, that as in other thermometersof this class, the amount of mercury employed will depend upon the sizeof the bulb at and the size of the capillary tube and that the necessaryscale or scale marks are provided in the usual manner as indicated inFig. 8.

By the herein described process I am enabled to produce thermometers ofthe class specified much more quickly and at a much lessexpense than washeretofore possible, and while I have shown and described the method ofprocedure which I prefer, my invention is not limited 'to theexactdetails thereof and changes therein and modifications thereof maybe made within the scope of the appended claims, without departing fromthe spirit of my invention or sacrificing its advantages.

Having fully described my invention,

what I claim as new and desire to secure by Letters Patent, is

1. The process herein'described of forming a thermometer which consistsin providin a capillary tube, and a casing tube one enfi of which 1stapered, forming a bulb on one end of the capillary tube, inserting saidcapillary tube into the casing tube so that the bulb closely fits thetapered portion thereof, heating the tapered portion ofthe casing tubeand the bulb, blowing through the capillary tube to rupture the bulband'expand the walls thereof and form an elongated bulb member and thenclosing the casing tube at the end of said bulb member to form thecomplete thermometer bulb.

2. The process herein described in forming a thermometer which consistsin providing a capillary tube and a casing tube, forming a bulb memberon one end of the capillary tube, inserting said capillary tube into thecasing tube, heating said casing tube and bulb member to a plasticcondition, blowing into the capillary tube to expand and rupture thebulb member and to unite the side walls thereof with the walls of thecasing tube and closing the bulb end of the casing tube and the bulbmember to form a complete thermometer bulb.

3. The process herein described of forming a thermometer which consistsin providing a capillary tube and a casing tube, forming a bulb on oneend of the capillary tube, the outside diameter of which is the same asthe inside of a part of said casing tube, inserting said capillary tubeinto the casing tube, heating said casing tube and bulb to a plasticcondition, blowing into one end of the capillary tube to expand andrupture the bulb and form an open elongated bulb member within thecasing tube and then closing the open end of said bulbmember to form acomplete thermometer bulb.

4. The process herein described of forming a thermometer which consistin providing a capillary tube and a casing tube, one end portion of thecasing tube bein reduced, forminga bulb on one end 0 the capillary tube,inserting said end of the capillary tube into the casing tube until thebulb thereon fits the reduced end portion thereof, heating said reducedend portion of the casing tube and said bulb, blowing into the capillarytube to rupture said bulb and expand the walls thereof into engagementwith the walls of the casing tube and to form in said casing tube anelongated open bulb member, sealing the end of the capillary tubeopposite the bulb member, pouring a predetermined amount of liquidsubstance into saideopen bulb member, marking the casing tube todetermine the point of the closure thereof, and heating and closing saidcasing tube to form a complete thermometer bulb.

In testimony that I claim the foregoing as my invention I have signed myname in presence of the subscribingwitnesses this 25th day of June,1917.

FRANK J. BERBERICH. Witnesses:

C. E. MULREANY, H, E. THOMPSON.

